| Summary: | <p style="text-align: justify !important;"><span><span lang="pt-BR">A baixa disponibilidade de P e o estresse hídrico estão entre os fatores que mais têm limitado a produção agrícola em solos de regiões tropicais. Com base nisto, conduziu-se um experimento, com o objetivo de avaliar o efeito do estresse hídrico e de doses de fósforo no acúmulo de nutrientes na parte aérea de plantas de sorgo (Sorghum bicolor (L.) Moench.), cultivar BR-304, de ciclo médio. O delineamento experimental foi o de blocos casualizados, em esquema fatorial 2x4, com 4 repetições, sendo dois regimes hídricos (com e sem estresse hídrico) e quatro doses de fósforo (0 mg dm</span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span lang="pt-BR"><span><span><span>-3 </span></span></span></span></span></span></sup></span></span><span><span lang="pt-BR">,</span></span><span><span lang="pt-BR"> 50 mg dm, 100 mg dm</span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span lang="pt-BR"><span><span><span>-3</span></span></span></span></span></span></sup></span></span><span><span lang="pt-BR"> e 150 mg dm</span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span lang="pt-BR"><span><span><span>-3</span></span></span></span></span></span></sup></span></span><span><span lang="pt-BR"> ). As plantas foram mantidas em vasos com capacidade para 9 kg de solo e o estresse hídrico foi imposto aos 45 dias após a emergência e persistiu até que fossem observados a parada do crescimento e o enrolamento das folhas do ápice. O estresse hídrico reduziu o acúmulo de K na parte aérea das plantas e a adubação fosfatada proporcionou aumento na absorção de N, P, Ca, S, Mn e Fe e redução na absorção de Zn. O fornecimento de P acima de 125 mg dm</span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span lang="pt-BR"><span><span><span>-3</span></span></span></span></span></span></sup></span></span><span><span lang="pt-BR"> causou redução no acúmulo de macronutrientes nas plantas de sorgo.</span></span></p> <p class="western"><span style="color: #000000;"><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span><span><span lang="pt-BR"><br />PALAVRAS-CHAVE: Sorghum bicolor (L.) Moench.; tolerância à seca; nutrição mineral; forrageira.</span></span></span></span></span></span></p><br /><br>Low phosphorus availability and water stress are among the factors that have limited agricultural yield in soils of tropical regions. Based on that, an experiment was carried out to evaluate the effect of water stress and phosphorus levels on the nutrients accumulation in the shoots of sorghum plants (Sorghum bicolor (L.) Moench.), BR-304 mid-cycle cultivar. The experimental design was randomized blocks arranged in a 2x4 factorial scheme, being two water regimes (with and without water stress) and four phosphorus levels (0 mg dm-³, 50 mg dm-³, 100 mg dm-³, and 150 mg dm-3), with 4 replications. Plants were kept in pots (up to 9 kg of soil) and water stress was imposed 45 days after emergence, and persisted until growth stopped and apical leaves curled. Water stress reduced K accumulation and phosphorus fertilization increased the N, P, Ca, S, Mn, and Fe, and reduced the Zn absorption. The supply of P above 125 mg dm-3 reduced macronutrients accumulation in sorghum plants.<br /><br />KEY-WORDS: Sorghum bicolor (L.) Moench.; drought tolerance; mineral nutrition; forage plant.
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